What is anastrozole?

Anastrozole lowers estrogen levels in postmenopausal women, which may slow the growth of certain types of breast tumors that need estrogen to grow in the body.

Anastrozole is used to treat breast cancer in postmenopausal women. It is often given to women whose cancer has progressed even after taking tamoxifen (Nolvadex, Soltamox).

Anastrozole may also be used for purposes not listed in this medication guide.

What is the most important information I should know about anastrozole?

Anastrozole is used to treat breast cancer in postmenopausal women. It is often given to women whose cancer has progressed even after taking tamoxifen (Nolvadex, Soltamox).

Do not use anastrozole if you are pregnant. It could harm the unborn baby.

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Anastrozole may not work as well if you take it together with estrogen medication (such as hormone replacement therapy, estrogen creams, or birth control pills, injections, implants, skin patches, and vaginal rings).

Anastrozole may increase your risk of a stroke or blood clot. Call your doctor at once if you have sudden numbness or weakness, (especially on one side of the body), sudden severe headache, slurred speech, or problems with vision or balance.

What should I discuss with my healthcare provider before taking anastrozole?

You should not use this medication if you are allergic to anastrozole, if you are breast-feeding a baby, or if you have not yet completed menopause. Anastrozole is not for use in men or children.

To make sure anastrozole is safe for you, tell your doctor if you have:

heart disease;

circulation problems;

a history of stroke or blood clot;

severe liver disease;

high cholesterol; or

osteoporosis or low bone mineral density.

Anastrozole can decrease bone mineral density, which may increase your risk of developing osteoporosis. Your bone mineral density may need to be tested before and during treatment with anastrozole.

Do not use anastrozole if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

It is not known whether anastrozole passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using anastrozole.

You may need to take a pregnancy test before using anastrozole, to make sure you are not pregnant.

How should I take anastrozole?

Anastrozole is usually taken once per day. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

You may take anastrozole with or without food.

You may need to keep taking this medication for up to 5 years. Follow your doctor's instructions.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking anastrozole?

This medicine can pass into body fluids (including urine, feces, vomit, semen, vaginal fluid). Patients and caregivers should wear rubber gloves while cleaning up body fluids, handling contaminated trash or laundry or changing diapers. Wash hands before and after removing gloves. Wash soiled clothing and linens separately from other laundry.

Body fluids should not be handled by a woman who is pregnant or who may become pregnant. Use condoms during sexual activity to avoid exposure to body fluids.

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Anastrozole side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

signs of a stroke--sudden numbness or weakness (especially on one side of the body), sudden severe headache, slurred speech, problems with vision or balance; or

severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

What other drugs will affect anastrozole?

Anastrozole may not work as well if you take it together with an estrogen medication (such as hormone replacement therapy, estrogen creams, or birth control pills, injections, implants, skin patches, and vaginal rings). Before you start taking anastrozole, tell your doctor if you also take tamoxifen or estrogen.

Other drugs may interact with anastrozole, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

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Where can I get more information?

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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